body{

    margin: 0%;
    padding: 0%;
    min-height: 100vh;
    background-color: #ffde59;
    font-family: "open sans", Verdana, Geneva, Tahoma, sans-serif;

}

body, .nav, .menu {

    display: flex;
    justify-content: center;
    align-items: center;
}

.nav{

    position: relative;
    background-color: #fff;
    padding: 20px;
    transition: 0.5s;
    border-radius: 50px;
    overflow: hidden;
    box-shadow: 0 8px 15px rgba(0, 0, 0, 0.2);
    

}

.menu{

    margin: 0;
    padding: 0%;
    width: 0;
    overflow: hidden;
    transition: 0.5s;

}


nav input:checked ~ .menu{

    width: 450px;


}

.menu, li {

    list-style: none;
    margin: 0 10px;

}


 .menu, li a {

    text-decoration: none;
    color: #666;
    text-transform: uppercase;
    font-weight: 600;
    transition: 0.5s;

}

 .menu, li a:hover{

    color: #161919;
}

 .nav input {

    width: 40px;
    height: 40px;
    cursor: pointer;
    opacity: 0;
}

 .nav span {

    position: absolute;
    left: 30px;
    width: 30px;
    height: 4px;
    border-radius: 50px;
    background-color: red;
    pointer-events: none;
    transition: 0.5s;
}

 .nav input:checked ~ apan {

    background-color: red;
}

 span:nth-child(2) {

    transform: translateY(-8px);

}

 input:checked ~ span:nth-child(2) {

    transform: translateY(0) 
    rotate(-45deg); 

}

 span:nth-child(3) {

    transform: translateY(8px);

}

 input:checked ~ span:nth-child(3) {

    transform: translateY(0) rotate(45deg);
}